Readily changeable die assembly for power presses



Aug. 15, 1961 v. GEORGEFF READILY CHANGEABLE DIE ASSEMBLY FOR POWERPRESSES Filed Aug. 16, 1956 6 Sheets-Sheet 1 INVENTOR. ZS/L 6EOA 6FFTTORNEY Aug. 15, 1961 v. GEORGEFF 2,996,025

READILY CHANGEABLE DIE ASSEMBLY FOR POWER PRESSES Filed Aug. 16, 1956 6Sheets-Sheet 3 TORNEY Aug. 15, 1961 V. GEORGEFF READILY CHANGEABLE DIEASSEMBLY FOR POWER PRESSES Filed Aug. 16, 1956 6 Sheets-Sheet 4 TI L3INVENTOR. Wis/L 660,965?

, A OPN EY Aug. 15, 1961 v. GEORGEFF READILY CHANGEABLE DIE ASSEMBLY FORPOWER PRESSES Filed'Aug. 16, 1956 6 Sheets-Sheet 5 INVENTOR.

1425/4 GEORGE/ F A ORNEY Aug. 15, 1961 v. GEORGEFF 2,996,025

READILY CHANGEABLE DIE ASSEMBLY FOR POWER PRESSES Filed Aug. 16, 1956 6Sheets-Sheet 6 INVENTOR. Wis/L GEORGEFF BY MtEQw ATTORNEY Fig ii UnitedStates Patent O 2,996,025 READILY 'CHANGEABLE DIE ASSEMBLY FOR POWERPRESSES Vasil Georgelf, La Grange Park, Ill., assignor to Danly MachineSpecialties, Inc., Chicago, 111., a corporation of Illinois Filed Aug.16, 1956, Ser. No. 604,437 5 Claims. (Cl.-11349) My invention relatesto. a. readily changeable: die. assembly for power presses and more.particularly to an assembly which permits the. diesv used on a press tobe. changed in a rapid, convenient and expeditious manner.

In operation of. a power press, one. of the mostdiflicult. and. timeconsuming, operations which must be. performed is. changing the presssetup? when. a new part is. to be produced on the. press. In the.courseof this changeover; the. old dies must be removedfromthe pressand. the new dies must be accurately locatedon the press bed so that theupper die may be secured to the press. slideand the lower die may besecured to the. press bed. The labor cost. of this operation is high asa result of the: high. hour- 15 wage. rate of skilled die setters. Owingto the high cost. of. setting upa press to produce a part, manufacturersmake large runs of a singlepartbefore changing the setup of. a. press.While this expedient saves. labor, it introduces the. necessity ofstoring and handling a very large numher ofv parts- Imbalances in. themanufacturers inventory result. In the manufacture of consumer goods,frequent model changes render obsolete many of the parts previously run,resulting in loss to the manufacturer. One solution to the problem is toprovide a large number of presses, each, using a different set. of dies.This. solution clearly is an uneconomical one.

It has been suggested in the prior art. that the. dies to be assembledon the. press be nested and placed on tracks. which are. run into thepress bedto permit the dies to be secured to the press slide and bed.Such a system has never been practicable in the prior art because of thedifliculty of locating the dies properly and. the. difficulty ofsecuring the dies to the press bed and to the press slide. Thevdifliculty of securing a die to the press drawing slide is particularlyevident in a press in which the drawing slide is mounted within a blankholderv slide.

I. have invented a readily changeable die assembly for power presseswhich permits the dies of a. press to be. changed in a rapid,convenient, and expeditious manner. My assembly includes means-foraccurately positioning a die set run into the press. bed to permit the:diesv to be secured to the press inner slide and bed. I provide myassembly with means for rapidly and simply securing the dies to thepress bed. My assembly permits the setup of a. press to be changed backand forth between two setups without the high labor cost involved insetting up operationsin the prior art.

An object of my invention is to provide a readily changeable dieassembly for a power press which permits the press dies to be changed ina rapid, convenient, and expeditious manner.

Another object of my invention is to provide. a readily changeable dieassembly for a power press which-accurately positions a die set-runinto. the: press bed to perunit the dies to secured to the press slideand the press bed.

A further object of my invention is to provide a readily changeable dieassembly for a power press including means for rapidly and simplysecuring a die to the press drawing slide.

Yet another object of my invention. is. to provide a readily changeabledie assembly for av power press which permits the press setup to bechanged back and forth 2. between two setups without the highlabor costsinvolved in changing dies in the prior art.

Other and further objects of. my invention will appear from thefollowing description:

In. general my invention contemplates the. provision of a readilychangeable die assembly for a power press having a frame and a bed and adrawing slide carried by the frame. for reciprocation with respect tothe bed. My assembly includes a movable member. which may be a bolsteror a ring carrying a bolster. I secure the lower die of a die set,including any upper die adapted to be: secured. to the press slide, tothe bolster. A track supports the member for movement from a locationadjacent the press to a: position over the press bed. I provide meansfor locating the member accurately on; the press bed to permit thevbolster or; bolster carrier to be secured to the press bed and topermit. the upper die: to be se.- cured to the press slide. My assemblyhas. means for rapidly and. simply securing the. upper die to the. pressdrawing slide. When. the setup of a. press with which my assembly isused is to be changed, the movable member and dies in the. press: are.released and run out of the press bed. and another member carrying thenew die set is run into the. press bed. I provide. drive means forrunning the movable. member into and out of the press.

In the accompanying drawings which form part of the instantspecification and which are to be read in conjunction. therewith and inwhich like reference numerals are used to indicatelike. parts in thevarious views:

FIGUREl is a perspective view of a powerpress employing my readilychangeable die assembly for power presses with parts broken away.

FIGURE '2 is a fragmentary front elevation of a power press employing myreadily changeable die assemblyfor power presses showing a bolster on acarrier ring.

FIGURE 3 is. a sectional view of a power press employing my readilychangeable die assembly for power presses taken along the line 3-3 ofFIGURE 2, and showing a die set in place on a bolster.

FIGURE 4 is a perspective view of a pair of bolster carrier rings of myreadily changeable die assembly for power presses with parts removed.

FIGURE 5 is a fragmentary sectional view of my readily changeable dieassembly for power presses taken along the line 5--5 of FIGURE 3 anddrawn on an en larged scale.

FIGURE 6 is a fragmentary sectional view of my readily changeable dieassembly for power presses in a position of the bolster carrier ringwhere the bolster is not located over my positioning means.

FIGURE 7 is a sectional view of my readily changeable die assembly forpower presses taken along the. line 7-7 of FIGURE 5.

FIGURE 8 is a fragmentary sectional. view of my readily changeable dieassembly for power presses taken along the line 8-8 of FIGURE 3 anddrawn on an en'- larged scale.

FIGURE 9 is afragmentary sectional view' of. one form olgdmeans forsecuring an upper die to the press drawing 5 e.

FIGURE 10 is a fragmentary top plan view taken along the line- 10-10 ofFIGURE 9.

FIGURE 11- is a fragmentary bottom plan view taken along the line I I-IIof FIGURE 9.

FIGURE 12 is a fragmentary sectional view of" another form of my meansfor securing an upper die to-the press drawing slide.

FIGURE 13 is a fragmentary elevation of the. form of my means forsecuring the inner slide shown in FIGURE 12 taken. along the line 13-13of; FIGURE.v 12-.

Referring now to FIGURES l to- 3 of the drawings, the power press withwhich my readily changeable die assembly is used includes a frame,indicated generally by the reference character 10, having a front 12, aback 14, and sides 16 and 18. The press includes a bed 20 to which mybolster, to bedescribed hereinafter, is adapted to be secured. Arespective inner slide 22 and a blank holder slide 24 are mounted forreciprocation with respect to bed 20 in frame in a manner known to theart. Respective openings 26 and 28 in the front 12 and rear 14 of thepress provide access to the area of the press between the slides 22 and24 and the bed 20. In order to permit entry of a bolster, to bedescribed hereinafter, into the press from either side, I provide therespective sides 16 and 18 with openings 30 and 32. Four respective uprights 34, 36, 38, and '40 having a hollow, rectangular cross-sectionare disposed at the respective corners of the press frame and separatethe side openings of the frame from the front and rear openings. Thepress tie rods 42, 44, 46, and 48, the function of which is known to theart,

4 unit. I fix a rack bar 90 formed with teeth 92 to the side 58 ofcarrier 56 by an convenient means such as welding or the like.

As can be seen by reference to FIGURES 2 to 4, frame 10 carries abracket 94 which supports a motor 96 which drives a shaft 98. Shaft 98carries for rotation with it a gear 100 which drives a pinion 102 fixedon a shaft 104 for rotation with the shaft. Any convenient means isemployed to support shaft 104 for rotation on the frame 10. The end ofshaft 104 remote from pinion 102 carries for rotation with ita pinion106 adapted to engage the teeth of bar 90 to drive the connectedcarriers 54 and 56. It is to be understood that a similar drive could beprovided for single unconnected bolsters.

Referring now to FIGURES 1 to 3 and 8, a plurality of bolts 108 disposedin vertical slots 110 in the sides of the bolster 112 pass through theholes 68 in the carrier sides 58 and 60 and into grooves 64. Nuts 114are extend from top to bottom of the press through the respectiveuprights 34, 36, 38, and 40. My construction of the press with uprightshaving a hollow, rectangular crosssection gives the press framesuflicient rigidity to withstand the shocks incident to its operationwhile permitting bolsters, to be described, to be run into the pressthrough the press sides.

A pair of respective raised tracks or rails 50 and 52 extend outboardfrom the bed through the side openings and 32. Any convenient means suchas a table or the like, not shown for purposes of clarity in exposition,supports the lengths of tracks 50 and 52 outboard of the press sides 16and 18.

- In FIGURES l I have shown a form of my invention for use with presseshaving no die cushions including respective movable bolsters 49 and 51carryingdie sets, to be described hereinafter. In presses provided withdie cushions, die pins must be permitted to extend a distance below thebolster. Referring now to FIGURES 2 to 7, in order to permit movement ofthe bolster and pins into threaded on bolts 108 to secure the bolster112 to the carrier ring. The lower die 117 of a die set has guide posts116, two of which are shown, on which the. upper die 118 of a die set isplaced. As is known in the art, posts 116 support the upper die 118 onthe lower die 117 and position upper die 118 properly on the lower die.

and out of the press, I have provided my assembly with bolster carrierrings, indicated generally by the respective reference characters 54 and56. Since the details of the construction for supporting movablebolsters 49 and 51 and carrier rings 54 and 56 on the rails and formoving the bolsters or rings into and out of the press are the same forboth the bolster and the rings, for purposm of simplicity I willdescribe these structures in connection with the rings only. Each of therespective sides 58 and 60 of each carrier 54 and 56 is formed with apair of spaced recesses 62. A longitudinal groove 64 runs along thelength of each of the sides 58 and "60 to provide a flange or lip 66 bymeans of which the carrier may be secured t'o'the press bed in a mannerto be described. A plurality of bolt holes 68 leading from the uppersurfaces of carriers 54 and 56 into the grooves 64 permit assembly of abolster to the carrier ring in a manner to be described.

Referring now to FIGURES 5 to 7, a plurality of stub shafts 70 fixed inthe sides 58 and 60 of the carriers extend into the recesses 62 andcarry bushings 72 which rotatably support wheels 74. I form each of thewheels 74 with a peripheral groove 76. Each of the carriers 54 and 56normally rests by means of its wheels 74 on the rails 50 and 52 with therails in the wheel grooves 76. It will be seen that rails 50 and 52guide the carriers in their movement into and out of the press in amanner to be described.

If desired, I may connect my carriers for movement as a unit to permit anew die set to be moved into the press while the set being replaced ismoved out of the press. Referring again to FIGURE 4, I form the carrier56 with a pair of elongated connecting arms 78 and 80 having bifurcatedends. The bifurcated ends of arms 78 and 80 fit loosely over projections82 and 84 formed on the carrier 54. Pins 86 and 88 pass through thebifurcated ends of arms 78 and 80 and through the projections 82 and 84to connect carriers 54 and 56 for movement as a In the form of myinvention shown in FIGURES 2 to 7 the lower die 117 is secured to thebolster 112 in a conventional manner, as by bolts or the like. Themovable bolsters 49 and 51 shown in FIGURE 1 are constructed similarlyto carrier rings 54 and 56 to permit them to be secured tothe press=bed. Lower dies 117 are secured to the movable bolsters of FIGURE 1 ina conventional manner. It is to be understood that where the press withwhich my die assembly is used is of the type which is provided with adie cushion and die pins, it is necessary that I use separate movablecarrier rings 54 and 56 to which the bolsters 112 are secured. When thepress with which my assembly is used has a solid bed and no die cushion,the bolster plates themselves imay be provided with wheels to permitthem to be moved into the press and no separate carrier rings arenecessary. I have shown such bolsters 49 and 51 in FIGURE 1. That is,the movable bolsters 49 and '51 shown in FIGURE 1 for use with a solidbed press are alternative to the movable carrier rings '54 and 56 towhich respective bolster plates 112 are secured.

In theposition of the parts shown inFIGURE l, a first die set carried bythe bolster 49 is over the press bed and a second die set carried by thebolster 51 is positioned adjacent the press side 18 outboard of thepress. When it is desired to employ the set of dies carried by bolster51, the bolster 49 and the upper die carried thereby are first freed.Motor 96 is energized to drive pinion 106 to move bolster 49 away fromthe press and to move bolster 51: into position over the press bed.

- In the course of this operation, both bolsters are supported on rails54} and 52. Motor 96 is energized until bolster 56 is approximatelypositioned over the press bed. It is to be understood that one of a pairof unconnected bolsters could be run out of the press and the otherbolster carrying a new set could be run in in separate operations.

Referring now to FIGURES 2, 3, 5, and 7, I form each of the tracks 50and52 with a pair of spaced, vertically-displaceable sections 120 locatedover the press bed. Each section 120 is secured by means such as weldingor the like to a piston 122 disposed in a cylinder 124 formed in thepress bed. A plurality of passages 126 in the bed provide a means bywhich fluid under pressure may be supplied to cylinder 124, to actuatethe pistons 122 to raise the sections 120 of track to the level of thetracks 50 and 52. A stop ring 128 adjacent the top of a cylinder 124 isengaged by a shoulder 130 on the associated piston 122 to limit theupward movement of the piston under the influence of fluid underpressure fed to the cylinder. When one carrier such as carrier 56 is tobe moved into the press, and another carrier,

easeas such as the carrier 54, is to be moved out of the press, asdescribed above in connection with the movable bolstemof FIGURE 1, fluidunder pressure is supplied by any convenientmeans known to the art topassages 126- to raise sections 120to the level of the tracks 50 and 52.Motor 96 is energized to drive the carriers until the wheels 74 ofcarrier 56 are positioned over the track sections 120. In this positionof the parts, the carrier is approximatelypositioned to be secured tothe press bed and the upper die 118 is likewise approximately positionedto be. secured to the drawing slide 22. It is necessary, however, thatthe carrier be accurately positioned before the parts are secured forpress operation. After the carrier has thus been approximatelypositioned, the fluid is exhausted from cylinders 124 to permit pistons122 to be drivendownwardlyin their cylinders under the influence of theweight of the carrier and die set. When this isaccomplished, the wheels74 sink with the sections I until the carrier rests on the press bed 20.In the course of this movement, it the carrier isnot exactly positioned,the wheels 74 engage an edge of the respective discontinuities formed bymovable track sections 1-20 and the carrier is shifted to the correctposition. As can be seen by reference to FIGURES 3 and 8, I may employlocating buttons 123 formed on the bed 20" and adaptedto engage inrecesses 125 formed in the bottom of carrier 56 or in the bottom ofamovable bolster; It is to be understood that the length of a trackdiscontinuity formed by a sectoin 120 is such that when the carrier isproperly positioned, the entire weight of the carrier and die assemblyis supported on the press bed and while the wheels 74 may engage trackdiscon tinuity edges, the wheelssupport no weight; It is to be notedfurther that the connection provided by arms 78- and 80 andprojections82 and 84 between the carriers 54 and 56, if employed, permits thecarrier disposed over thepress bed to move downwardly when properlypositioned on the bed.

Referring again to FIGURE 8, when the carrier is properly positioned, anumber of clamps 132 extending over the flange 66 on the carrier aresecured by bolts 134 to the press bed. Thus, the carrier and bolster 112carried: by the carrier ring are held in position on the press bed 20.The movable bolsters of FIGURE 1 similarly are secured to the press bed.

Referring to FIGURES 2 and 9 to 11, the inner slide 22 supports anumberof drive motors 136. Each motor 136 drives a shaft 138 carrying a pinion140 for rotation with it. Pinion-1140 drivesa gear 142, the hub 144 ofwhich isrotatably carried on bushings 146 mounted on astub shaft 148fixed in a housing 150 on the inner slide. I form hub 144 with a pinion152 which engages a gear 154 rotatably supported in housing 150 on ahearing plate 156; A clamping bolt, indicated generally by the referencecharacter 158 has a threaded shank 169 and a rectangular head 162. Theend 164 of shank 160 remote from head 162 is reduced along a diameter toform a rectangular cross-sectional area, the major axis of which is atright angles; to the major axis of the crosssectional area of head 1 62.The threaded shank 160 of belt 158- is threaded into the threaded axialbore 166 of gear 154. End 164 is disposed in an opening 168 in the topof housing 150. I form opening 168 with a pair of stops I70 and 172adapted to be engaged by end 164.

6 head 162' isdisposed to permit: its entry into the; slot 174. When thedrawing slide 22 has been moved, as described. above, to insert head 162through opening 174 and into a bore 179 on the upper die, the directiondrive of motor 136 is reversed. In this direction of drive; of themotor, bolt 158 moves with gear 154 until thebolt: assumes the full-lineposition shown in FIGURES 9 and. 10; In this position of end 164,further rotation of bolt 158i with gear 154 is prevented. At the sametime, the:

- major axis of head 162 is at right angles to the major axis of opening174. Upon further rotation of gear 154, bolt 158 is drawn upwardly asviewed in FIGURE. 9 tosecure the upper die firmly to the inner slide.When it is desired to unclamp the upper die, the direction of drive ofthe motor 136 is reversed. In this direction of drive of the motor, theupper die is released and bolt 158 is drivenv to align head 162 withopening 174' to? permit withdrawal of inner slide 22 from the upper die-1'18'. It is" to be understood that as many clamping bolts- 158 as arenecessary to provide a firm engagement between the upper die and innerslide maybe employed. It will be seen thatbolts 158 provide a means forse-' curing the upper die to the. inner slide without the necessity ofinserting a tool inside the blank holder slide.

Referring now to FIGURES l2 and 13, I have shown an alternate means forsecuring the upper die to the inner slide. In this form of my securingmeans, I' employ the same clamping bolts 158 as are shown in theform ofmy securing meansin FIGURES 9 to 11. I replace gear 154 with a worm gear180 adapted to be driven by aworm 1 82. One end 184 of worm 182 isadapted to be engaged by an air operated tool to drive the worm torotate gear 180' to secure the upper dietothe slide 22. opening 186 inthe blank holder slide 24 provides access to worm end 184.

In operation of my: readily changeable die set assembly' for powerpresses; when the press is to be set up, fluid under pressure issupplied to cylinders 124 to raise the movable track sections 120 to thelevel of tracks 50 and 52. A bolster such" asthe bolster 49, or acarrier such as carrier 54- carrying adie set is run along the tracksinto the press over the press bed. When the. bolster carrying: the dieset has been approximately positioned with respectto the movable tracksections 120, fiuid is exhausted from cylinders 124 and the bolster anddies sink under the influence of gravity until they are supported on thepress bed 20. In the course of. this; action, the bolster is notcorrectly positioned, wheels. 7-4 engage edges of the discontinuitiesformed. by the movable sections 120to shift the" bolster and dieassembly' and die set to the correct position. When the bolster iscorrectly positioned, clamps 132 are assembled on the bed to hold thebolster and the lower die in position on the bed. The drawing slide 22is lowered with the heads 162 of bolts 158" alignedwith openings 174until the heads enter bores 179. Motors 136 then are driven to move ends164 to the full-line position shown in FIG- URES' 9 and 10. Continued.rotation of. the motors 136' draws bolts 158' up to secure the upper die118 firmly to the inner slide 22. Alternately to the form of the upperdie clamping means shown in FIGURES 9 to II, the form; of clamping meansshown in FIGURES 1'2 and 13 maybe employed. It: will be understood thatif the press with which my die assembly is used includes no blank holderslide, common bolts may be used to secure the. upper die to the drawingslide. After the upper die 118 has been securedv to the drawing slideand the carrier ring 54 supporting a bolster 112. and lower die 117 orthe movable bolster 49 supporting the lower die 117 has been secured tothe press bed, the drawing slide may be moved upwardly to move the upperdie. 118 away from. the lower die 117'. Inthe. course of this action theupper die 118. moves. away from. the. lower die. 117 along thein,FIGURES 9 and. 1.0. In. this position of end 164. guideposts 116..

"'When it is desired to change the press setup'from that corresponding,for example, to the die set carried by bolster 49 to that, for example,corresponding to the die set carried by bolster 51, bolts 158 areactuated to release the upper die from the inner slide and thebolster 49is released from the press bed. Fluid under pressure is supplied tocylinders 124 to raise track sections 120 and bolster 54 and its dieset. Motor 96 is energized to drive pinion 106 to move bolster 49 out ofthe press and advance bolster 51 into the press. Where unconnectedbolsters are employed, these operations are performed separately. Whenbolster 51 is approximately positioned with its wheels 74 over sections120, the fluid in cylinders 124 is exhausted and the bolster is properlylocated. The bolster and upper die may then be secured to the respectivepress bed and drawing slide as described hereinabove. The operation ofthe form of my invention including movable bolsters 49 and 51 shown inFIGURE 1 is thesame as that of the form of my invention includingcartiers 54 and 56 shown in FIGURES 2 to 7.

; While I have shown and described an assembly including only twomovable bolsters, it will be readily understood that a train ofbolsters, each of which carries a different die set, may, if desired beemployed. It is to be understood further that the die set on bolster 49may be changed while bolster 51 is in use and vice versa.

It will be seen that I have accomplished the objects of my invention. Ihave provided a readily changeable die assembly for power presses bymeans of which the setup or a press may be changed in a rapid,convenient, and ei rpeditious manner. The setting-up operation with myassembly does not require the expensive labor involved in setting up apower press in the prior art. My assemblyincludes meansfor locating adie set accurately on the press bed. I provide my assembly with meansfor rapidly and simply securing the upper die of a die set to the pressdrawing slide. My assembly eliminates the need for employing a largenumber of presses where a great variety of short run parts are to bemade; It does not require a manufacturer to make long runs of smalldemand parts in order to save setup labor cost. a It will be understoodthat certain features and subcombinations are of utility and may beemployed without reference to other features and subcombinations. Thisis contemplated by and is within the scope of my claims. It is furtherobvious that various changes may be made in details within the scope ofmy claims without departing from the spirit of my invention. It istherefore to be understood that my invention is not to be limited to thespecific details shown and described.

Having thus described my invention, what I claim is:

1. In a metal Working press having a bed, a crown, uprights between thebed and crown and a draw slide vertically movable toward and away fromsaid bed,

mechanism for replacing die sets in said press compris-- ing, tracks onsaid bed arranged between opposed uprights and extending outwardly fromopposite sides of the press, first and second longitudinally alignedbolsters arranged in end to end relationship and connected tog'ether atadjacent ends, wheels for supporting said first and second bolsters formovement on said tracks, means for moving said bolsters on the tracksinto and out of the press, each bolster adapted to receive a die setthereon when outside of the press, said die sets including upper andlower dies, the lower die being secured tothe bolster when outside ofthe press and the upper surface of the upper die being adapted to beplaced in abutting relationship with the lower surface of said drawslide when the bolster and die set have been positioned in the press,means within the press for locating the bolster at a predeterminedposition in the press, fluid pressure means in said press bed for movingthe wheels between an upper position so that the bolster may move onsaid tracks and a lower position which lowers the bolster to the pressbed prior to the forming operation to give the bolster a firm foundationduring the press operation, clamping means in the press cooperable withlongitudinal grooves formed in the sides of the bolster for clamping thebolster in its lowered position to the bed, and means for securing theupper die to the draw slide when the bolster and die set have beenpositioned in the press and the draw slide lowered to abuttingrelationship with said upper surface of the upper die.

2. A readily changeable die assembly for a power press having a frameand a bed and a working slide mounted in the frame for reciprocationwith respect to the bed including in combination a movable member, diescarried by said member and comprising an upper die adapted to be securedto saidworking slide and a lower die adapted to be secured to saidmember, means supporting said member for movement from a locationadjacent said press to a position within said press over and above saidbed and means for locating said member on said bed in a located positionto permit said upper die to be secured to said working slide, saidsupporting means including wheels carried by said member, rails carriedby the bedof the press on which the wheels are adapted to rest, saidrails being formed with a plurality of movable sections within saidpress, said wheels being adapted to rest on said movable sections whensaid member is in position within said press, a plurality of fluidpressure cylinder and piston assemblies, means for supporting saidmoveable rail sections on said piston and cylinder assemblies, means foractuating said piston and cylinder assemblies to lower said member insaid located position to the pressbed prior to the reciprocation of theworking slide.-

3. A quick die change power press including in commination a frame, abed, a working slide mounted in; the frame for movement with respect tothe bed, a bolster, a pair of coacting dies carried by said bolster andcomprising an upper die adapted to be secured to the working slide and alower die, means supporting the bolster above the bed for movement froma first location adjacent said press to a second location over the bedat which the upper die may be secured to the slide, means for moving thebolster from said first location to said second location, saidsupporting means and said bolster coacting to guide said bolster along apredetermined path on said supporting means in its movement from saidfirst location to said second location, said supporting means comprisingmeans adapted to be actuated to lower said bolster toward said bed atsaid second location and means for actuating said lowering means tolower said bolster in said second location prior to the operation ofsaid slide.'

4. In a metal working press having a bed, a crown, uprights betweenthebed and crown and a slide vertically movable between the uprights,mechanism for easily and quickly replacing dies in said press therebyreducing press down time comprising, supporting means including tracksmounted on said bed and extending outwardly from opposite sides of thepress and between opposed uprights, a bolster movable on said tracks,said bolster adapted to receive thereon a die set having upper and lowerdies, means to secure the lower die of the die set to the bolster whenthe bolster is outside of the press, means for secur ing the upper dieof the die set to the slide after the bolster has been positioned withinthe press, means for driving the bolster along the tracks and into thepress with a die set thereon, said supporting means and said bolstercoacting to guide said bolster along a predetermined path in the courseof its movement into the press and locating means within the pressincluding means on said bed coacting with means on the bolster forprecisely locating the bolster at a predetermined position along thepress bed beneath the slide, said supporting means including meansoperable for lowering the bolster into intimate engagement with the bedprior to press operation thereby giving it a firm foundation.

5. In a metal working press having a bed, a crown, uprights between thebed and crown and a slide vertical 1y movable between the uprights,mechanism for easily and quickly replacing dies in said press therebyreducing press down time comprising, supporting means including tracksmounted on said bed and extending outwardly from opposite sides of thepress and between opposed uprights, a bolster movable on said tracks,said bolster adapted to receive thereon a die set having upper and lowerdies, means for securing the uper die of the die set to the slide afterthe bolster has been positioned within the press, means for driving thebolster along the tracks and into the press with a die set thereon, saidsupporting means and said bolster coacting to guide said bolster along apredetermined path on said supporting means from a position outside thepress to a position within the press above said bed and under saidslide, locating means within the press including means on said bedcoacting with means on the bolster for precisely locating the bolster ata predetermined position on the press bed beneath the slide, saidsupporting means comprising means for lowering the bolster to the bedinto intimate engagement therewith prior to press operation therebygiving it a firm foundation, and means for securing the bolster to thebed thereby assuring stability during operation.

References Cited in the file of this patent UNITED STATES PATENTS1,607,073 Gros NOV. 16, 1926 1,607,074 Gros Nov. 16, 1926 2,186,799iBoker Jan. 9, 1940 2,317,440 Cannon n Apr. 27, 1943 2,647,784Janiszewski Aug. 4, 1953 2,765,836 Niekelski Oct. 9, 1956

